Snippets of Shell code.

== Show every second line of a file ==
<code bash>
awk 'NR % 2 == 0' filename
</code>

<code bash iperftests.sh>
for server in `cat server.list`
do
 echo -e "Server: "$server
 ssh -T $server "iperf3 -s -D";
 for client in `cat server.list`
   do
    echo -e "Client: "$client
    ssh -T $client <<EOF
     iperf3 -c $server -n 50G -P 2 | tail -9
EOF
   done
  ssh -T $server "pkill iperf3";
done
</code>

Install tcptraceroute, then
http://www.vdberg.org/~richard/tcpping